1. Field of the Invention
The present invention relates to an adaptor device for a wrench. In particular, the present invention relates to an adaptor device that can be attached to a box end of a wrench, allowing the wrench to engage with a tool bit or socket and allowing easy removal of the tool bit or socket from the adaptor without causing disengagement of the adaptor from the wrench.
2. Description of the Related Art
FIG. 7 of the drawings illustrates a conventional adaptor 2 that can be attached to a box end of a wrench 1. A drive member 3 is mounted in the box end of to wrench 1 and includes an annular groove 8 in an inner periphery thereof for receiving a C-clip 4. The adaptor 2 includes an end engaged in the drive member 3 and retained in place by the C-clip 4. A receptacle 6 is defined in the other end of the adaptor 2. An annular groove 9 is defined in an inner periphery defining the receptacle 6, and a C-clip 7 is received in the annular groove 9. An end of a tool bit 5 is releasably engaged in the receptacle 6 with the C-clip 7 engaging with a retaining groove 50 in an outer periphery of the end of the tool bit 5. Thus, the wrench 1 can be used with a tool bit 5 through the use of the adaptor 2. It is noted that the retaining force provided by the C-clip 7 is greater than that provided by the C-clip 4, as the former has a smaller diameter. Thus, when removing the tool bit 5 from the adaptor 2 by means of applying force to the tool bit 5 in a direction indicated by the arrow in FIG. 8, it was found that the adaptor 2 was disengaged from the drive member 3, yet the tool bit 5 was still engaged in the receptacle 6 of the adaptor 2. As a result, the user must disengage the tool bit 5 from the adaptor 2 through another effort and then engage the adaptor 2 with the wrench 1. The procedure is troublesome and time-consuming when replacement of the tool bit 5 is required.
An object of the present invention is to provide an adaptor device that can be attached to a box end of a wrench, allowing the wrench to engage with a tool bit or socket and allowing easy removal of the tool bit or socket from the adaptor without causing disengagement of the adaptor from the wrench.
An adaptor device in accordance with the present invention comprises an adaptor and a retainer. The adaptor includes a first end removably mounted in a box end of a wrench and a second end releasably engaged with an object such as a tool bit. The retainer is fixed to the first end of the adaptor and includes at least two resilient retaining sections on an outer periphery thereof. A slit is defined between said at least two resilient retaining sections. The resilient retaining sections abut against an end of the box end of the wrench, thereby providing an engaging force between the resilient retaining sections and the end of the box end that is greater than an engaging force between the adaptor and the object.
The first end of the adaptor is inserted through the box end until the retainer is completely passed through the box end. The resilient retaining sections are compressed while passing through the box end. The resilient retaining sections resume their shapes after passing through and abut the end of the box end. Thus, the tool bit can be disengaged from the adaptor without causing disengagement of the adaptor from the box end of the wrench. Preferably, each resilient retaining section is convex in an intermediate portion thereof and extends in a direction perpendicular to a general plane of the retainer.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.